1. Field of the Invention
This invention relates generally to viewing systems and, more particularly, to an apparatus and method for providing spherical viewing in a cavity, such as an internal body cavity of a patient.
2. Description of the Related Art
Minimally invasive surgery (MIS) such as laparoscopic, endoscopic, hysteroscopic, and arthroscopic surgery (referred to hereafter generally as endoscopic surgery), is becoming more widely used because it is often less traumatic to the patient, generally involves less hospitalization time, less discomfort, and less risk to the patient, and is usually less costly than traditional open surgery.
The endoscopic surgery is generally preformed using elongate instruments slidably inserted through an opening into a body cavity. If the body cavity is accessible through a naturally occurring body orifice, the instruments may be inserted through that orifice. In cases where the body cavity is otherwise inaccessible, a small incision may be created in the patient to provide access to the area to be treated. A trocar sheath may be inserted in the incision, with the trocar heath configured to permit the slidable insertion and rotation of endoscopes and surgical instruments into the cavity.
An endoscope is generally used to view the inside of the body cavity. For example, an endoscope can be used to inspect the condition of the tissue lining a body organ, such as a human uterus. The endoscope can also be used to observe the manipulations being performed by surgical instruments positioned within the body cavity. Most current endoscopes provide a limited and fixed view, so that the surgeon typically must physically reposition the entire endoscope in order to change the endoscopic view within the body cavity, or remove the endoscope entirely and replace it with one having the desired angle of view. Such manipulations and replacements can be undesirable, since they can complicate the surgery and increase the risk of inadvertent damage to body tissue from accidental contact between the tissue and the endoscope.
Several previous designs have been proposed to permit individual endoscopes to vary their angles of view without requiring extensive movement of the endoscope. The small sizes of endoscopes, which can be on the order of 3 mm in diameter, place restrictions on such designs, and limit the options available. For example, complicated combinations of optics may be difficult to assemble in the small enclosure provided by the body of many endoscopes.
Therefore, those concerned with the development and use of endoscopic surgical systems and the like have long recognized the need for a system which is capable of enabling a surgeon to efficiently view large portions of internal cavities without requiring large manipulations or replacements of endoscopes during a procedure. Accordingly, the present invention fulfills these needs by providing an efficient and effective endoscope apparatus, selectively operable to permit a surgeon to view the majority of the internal area without having to replace or make major movements of the endoscope.
Briefly, and in general terms, the present invention provides a new and improved viewing system, apparatus, and method for viewing internal cavities, such as an internal opening in a human body.
The present invention provides an endoscope or similar viewing apparatus that permits near-spherical viewing of a cavity, such as an internal enclosure, a crevass, or other generally inaccessible area. The invention permits such viewing without requiring large movements of the endoscope. The apparatus includes a distal portion with distal viewing optics, such as reflectors or cameras, that collect images from the cavity interior. The images are then relayed to the proximal portion of the apparatus, where they can be viewed by a user or relayed to an external display.
By moving an internal reflector within the distal portion of the endoscope, the endoscope can vary its angle of view from 0 degrees (i.e., straight ahead from the endoscope distal end) to as much as plus or minus 180 degrees (i.e., looking back toward the proximal portion of the endoscope), depending on the particular design. Rotation of the endoscope distal viewing optics about the endoscope""s longitudinal axis, such as may be accomplished by rotating the entire endoscope about its longitudinal axis, when combined with the previously discussed angle-varying optical procedure, permits the endoscope to achieve near-spherical viewing of the interior of the body cavity, without requiring the endoscope to undertake any movement except a simple rotation about its longitudinal axis. Moreover, where the endoscope is surrounded by or otherwise includes an outer sheath that remains stationary during such rotations, the movement of the interior portions of the endoscope (to permit spherical viewing) can be conducted with the outer sheath remaining stationary, thus preventing any potential damage to tissue that may be in contact with the outer sheath.
The invention further provides improved feedback to the user regarding the line of sight along which the system is viewing. The feedback may be provided on a monitor or via directional control mechanisms, such as a rotator knob positioned on the endoscope.
These and other features of the invention will become apparent from the following detailed description, when taken in conjunction with the accompanying drawings.